Looking at the v1 versus v2 bags, and seems like the v1 bags are better (for me) with the placement of the handle on top, no webbing on the sides to limit how wide the top opening gets, etc.
But thinking about size, which always matters. Planning to use mostly as an EDC when I don't want to hold things in my pockets (e.g. keys, wallet, phone, etc.). If I bring camera gear, it'll most definitely be mirrorless (Fuji Xt2 with a few lenses). None of my Canon FF stuff because who wants to carry that weight on one shoulder? lol
Ideally, I would get the 5L for the smaller form factor but how much mirrorless gear can it hold? Would the xt2 and maybe three lenses fit (e.g. Fuji 10-24, 18-55, and 55-200)? B&H has a store display model of what looks to be v1 of the 5L for $70. They also have what looks to be v1 of the 10L for like $83. Only a $13 difference but not sure I like the usability of the two straps at the bottom on the 10L?
I've had the 5L version one sling for a few years and it's the bag I grab most often. I have thee version one 10L also. The 5 will just barely hold my Sony A7R4 with the 70-200 f4 lens, hood reversed. It's much more manageable with my Tamron 28-75 f2.8. Tightening up the strap lets the bag sit pretty securely against my back while hiking or bicycling. I did need to fold and sew the ends of the strap to keep it from backing out of the tensioners. I came very close to dropping my gear on the ground when the strap let go on me. It's been rock solid since my modification.
I'm not too familiar with the Fuji gear so I can't weigh in on it for sure but I think that the body with the three lenses are going to be a very tight fit.
The two straps on the bottom of the 10L really are only useful for cinching up the expandable outer pocket against the main body of the bag. The ends of the strap are folded over and sewn so that they don't unthread from the tensioners easily. I wish it were easier, it would be a good place to strap my tripod bag. Tons of space in the bag though, easy to over pack it and carry too much weight.
I have found the build quality of both bags excellent and the weather resistance to be very good too.
I'm a bit late to the party here, but I have that Fuji kit (XT4, 10-24, 18-55, 55-200) and just put everything in my 6L (which is similar to the 5L). I have the 55-200 on one side, the 10-24 on the other with the flap folded down, and the XT-4+18-55 in the middle, with its grip over the folded flap.
The X-T4 can also fit with the grip facing away from the wearer, which allows the 10-24's pocket to be full height (allowing me to instead fit something larger like the 80/2.8, if I wished). Doing this, the bag bulges away from me somewhat, making the zipper not as smooth. My experience with the PD Slings is that it's a bit of a pain to get bodies out when you put them in the bag this way, too.
I will say the PD Slings in general (and the 6L in particular) is a bit of a pain to get lenses out of the sides due to the small opening, especially if you're wearing gloves. I much prefer my old square-ish ThinkTank bags for rapid lens changes, but the Slings are really comfortable to wear, and my primary need for a bag is that it doesn't make my hate my camera after a couple hours of hiking.
I originally bought the 6L to carry a small Fuji primes kit. It does a good job at that, and it's OK with small zooms like the 18-55, too. It's the bigger zooms and shooting with hoods where you start cursing its curved design and small opening.
In the end, I got a 10L and use that almost exclusively. I like shooting with two bodies (I pair the X-T4 with an X100V or X-T30), and the 10L is not only more comfortable, but it's easier to get lenses in and out of, and I can easily carry my preferred two-camera prime kit (ie: X-T4 & X-T30 with 16/1.4, 35/1.4, 56/1.2, and a macro) without it being a pain to shoot out of. I don't find the added weight to be problematic, because the 10L sits flush to my body and with the cinch strap drawn tight and the bag across my back the weight almost "disappears".
Personally, I'd recommend the 5L or 6L if you're shooting with the small Fuji primes or the larger primes without hoods, and at most one medium-size zoom. Anything beyond that (your kit included) I prefer the 10L. I use the 10L for all my shooting these days, unless I have to bring water or my 500PF.
Maybe also take a look at the (better IMHO) PGYTech OneGo (10L) and the smallest Dulepro Explorer (B410N). Worthy of consideration.
I've just come back from a trip to Tibetan-Sichuan and the middle size Dulepro (450) was my daily camera bag - it was awesome, allowing instant access and great storage options (drone in the top and both cameras lined up by the quick access flap) with water-resistant YKK zips too, so light rain/drizzle wasn't an issue.
